1. Field of the Invention
The disclosure relates to a transparent developer, a developer housing, a development device, and an image formation apparatus, and is applicable, for example, to a developer, a developer housing, a development device, and an image formation apparatus to be used in an electrophotographic image formation apparatus or the like.
2. Description of Related Art
One type of electrophotographic image formation apparatus that is capable of forming color images is what is termed a tandem-type image formation apparatus (see Japanese Patent Application Publication No. 2013-117583). A tandem-type image formation apparatus includes an array of photoreceptor drums for different colors such as Y (yellow), M (magenta), C (cyan), and K (black) along an intermediate transfer belt, and sequentially transfers toner images (developer images) formed on the respective photoreceptor drums to the intermediate transfer belt so that the toner images (developer images) are superposed on one another to form a multilayer. The multilayer of the color toner images transferred to the intermediate transfer belt is secondarily transferred together on a record medium such as paper in a secondary transfer position.
In addition, tandem-type image formation apparatuses include those providing prints with partial glossiness (namely, spot gloss) by using a transparent toner in addition to a color toner. Such partial glossiness is formed by generating a difference in glossiness between color toner areas and transparent toner areas or a difference in glossiness between transparent toner areas and toner-less non-image areas.
When tandem-type image formation apparatuses use transparent toner in order to generate a difference in glossiness from the color toner areas in prints, it is necessary that a transparent toner layer and multiple toner layers of Y, M, and C colors be laminated on the intermediate transfer belt, and these laminated toner images be secondarily transferred together to a record medium.
In this case, a problem arises in that some laminated toner images may spread to cause blurred printing easily on record media. Particularly when transferring fine toner images such as line figures and letters to record media, toner spreading is so noticeable that the quality of the finally-obtained images is decreased.
A possible cause for such toner spreading is that the thickness of the laminated toner layers is too large to strongly hold the toner layers on the intermediate transfer belt, and therefore some of toner in an upper part of the toner layers spreads to the record medium surface before the application of a secondary transfer voltage.
Against this background, to prevent the toner spreading, it is desired to enable a strong holding of the toner layers on the intermediate transfer belt by reducing the thickness of the toner layers laminated on the intermediate transfer belt (i.e., reducing the amount of toner applied per unit area on the record medium).